Surgery for a patient can be painful and traumatic, particularly in the affected area of the patient's body. For spinal fixation systems, a necessary procedure often involves forming a hole in a pedicle of a vertebra in a patient's spine and inserting a spinal pedicle screw into the hole. Pedicle screws are advantageous in that they are strong and provide stability, however, care must be taken to avoid nerve impingement during formation of the holes and the placement of pedicle screws in the vertebral body. Some measures taken range from monitoring muscle reactions to electrically stimulating tissue to locate nerves in or adjacent the bone tissue during preparation of the hole and during insertion of the pedicle screw.
Some spinal procedures further require a force to be applied to one or more inserted pedicle screws to change the orentation of one or more vertebrae and/or to align the pedicle screw for connection with other components of a spinal fixation system. The application of additional forces on the pedicle screw can sometimes weaken or compress the bone surrounding the screw, potentially exposing neural elements to the pedicle screw. If the screw contacts an exposed nerve, impinges on the nerve, or becomes too close to the nerve root, pain and other implications for the patient may result.